1. Field of the Invention
This invention relates to headlight systems for motor cycles, which are arranged to adjust the orientation of the headlamp beam in such a way as to compensate for the lateral inclination of the motor cycle when travelling along a curved path.
2. Description of the Prior Art
Various such systems have already been proposed in my earlier U.S. Pat. Nos. 3,939,339 and 4,075,469. In U.S. Pat. No. 3,939,339, a system is proposed which senses the magnitude of the angle of lean of the motor cycle by means of an acceleration transducer comprising a mass which is movable under the control of a spring, in a direction which is generally vertical when the motor cycle is upright. Such an acceleration transducer cannot distinguish between inclination to the left and inclination to the right, and therefore some kind of additional mechanism has to be provided to ensure that the headlamp beam is adjusted in the correct sense to affect the necessary compensation. In U.S. Pat. No. 3,939,339, it was proposed to operate this mechanism in dependence on the direction in which the motor cycle handlebars are turned.
In U.S. Pat. No. 4,075,469, it is proposed to use a gyroscope system to detect both the magnitude and the sense of the inclination of the motor cycle. The use of a gyroscope system has the theoretical advantage that only a single sensing arrangement provides all the information that is needed.
However, it has been found that there are difficulties in providing a sufficiently accurate gyroscope system; also the gyroscope system may suffer from drift, resulting in orientation errors.
It is an object of the present invention to provide a headlight adjusting system employing a gyroscope system only to discriminate between inclinations to the left and to the right, and employing other means to detect the magnitude of the inclination of the motor cycle.